Good Day! Thank you for reaching out to the Community.
I understand your concern but since PowerSchool Learning has reached its end of life the option to export the materials from Learning is not available. I recommend working with the administrators in your school district to create those resources again.
Sorry to be the bearer of bad news, and as a former teacher I sympathize, but also as a former teacher it isn't PowerSchool's fault you had no redundancy of data on your curriculum. When I was teaching my gradebook alone existed in 4 different locations, not to mention all of my curriculum which lived on a flash drive, an external HDD, two separate HDDs on a local PC and a location in the Cloud.
This likely won't work but it might be worth a shot: